There’s a lot missing. The real number is actually a lot bigger. And we don’t know what it is.

The gap between what the city says it needs to spend over the next five years and the money it expects to have is $1.8 billion. That figure includes water and sewer pipes, major street repairs and storm water upgrades. It doesn’t include fixing all the city’s rundown buildings, including Balboa Park museums. The two oft-discussed megaprojects, a new Convention Center expansion and new Chargers stadium, didn’t make the list, but neither did the price tags to repair the existing Convention Center and Chargers stadium. And public works crews aren’t done evaluating all city facilities and sidewalks yet, and they will add those costs once that happens.

“The need will get greater,” said Tony Heinrichs, the city’s infrastructure chief.

Here’s a quick rundown of some big things missing from the city’s fix-it list:

Balboa Park

Last year, John Hogan, the operations manager for the Museum of Photographic Arts in Balboa Park, gave me a tour of all the things broken outside his building, which is known as the Casa de Balboa. It was a lengthy list. He showed me loose pieces of concrete near the edge of the roof, poorly done patchwork fixes where bee colonies had moved in and the growth of what appeared to be some sort of fungus.

“Things have only gotten worse,” Hogan told me this week.

Hogan took the house of horrors on the road, making a PowerPoint and showing it to anyone who would look.

All told, Balboa Park’s infrastructure needs have been estimated at $300 million. Most of that number isn’t included in the city’s infrastructure budget. Public works officials left out all facilities the city leased to someone else, including the park’s museums. The thinking was that lessees might have to make fixes on their own. Not all of these buildings fall within the public interest the way Balboa Park museums do. The Downtown Johnny Brown’s restaurant next to City Hall is one example.

The Old Stadium and Convention Center

As of four years ago, Qualcomm Stadium needed about $80 million in repairs, with electrical, mechanical and plumbing problems topping the list. Those costs didn’t make the city’s budget. Neither did the $36 million needed for fixes to the existing Convention Center, including a section the center’s spokesman said was “rotting.” Public works officials said these were left off because of the uncertainty surrounding the stadium situation and the ongoing development of a formal plan for Convention Center repairs.

The Missing Buildings and Sidewalks

The city’s only gone over about roughly half of the buildings it owns to see what needs to be repaired. It’s through about 80 percent of its sidewalks. Together, the unfunded needs on those two assets are already about $200 million. The city expects to get final numbers on sidewalks early this year and to finish its building assessment next year. Both will increase the city’s deficit.